OTSubcredential.cpp

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/************************************************************
 *
 *  OTSubcredential.cpp
 *
 */

// A nym contains a list of credentials
//
// Each credential contains a "master" subkey, and a list of subkeys
// signed by that master.
//
// The same class (subkey) is used because there are master credentials
// and subkey credentials, so we're using a single "subkey" class to
// encapsulate each credential, both for the master credential and
// for each subkey credential.
//
// Each subkey has 3 key pairs: encryption, signing, and authentication.
//
// Each key pair has 2 OTAsymmetricKeys (public and private.)

/************************************************************
 -----BEGIN PGP SIGNED MESSAGE-----
 Hash: SHA1

 *                 OPEN TRANSACTIONS
 *
 *       Financial Cryptography and Digital Cash
 *       Library, Protocol, API, Server, CLI, GUI
 *
 *       -- Anonymous Numbered Accounts.
 *       -- Untraceable Digital Cash.
 *       -- Triple-Signed Receipts.
 *       -- Cheques, Vouchers, Transfers, Inboxes.
 *       -- Basket Currencies, Markets, Payment Plans.
 *       -- Signed, XML, Ricardian-style Contracts.
 *       -- Scripted smart contracts.
 *
 *  Copyright (C) 2010-2013 by "Fellow Traveler" (A pseudonym)
 *
 *  EMAIL:
 *  [email protected]
 *
 *  BITCOIN:  1NtTPVVjDsUfDWybS4BwvHpG2pdS9RnYyQ
 *
 *  KEY FINGERPRINT (PGP Key in license file):
 *  9DD5 90EB 9292 4B48 0484  7910 0308 00ED F951 BB8E
 *
 *  OFFICIAL PROJECT WIKI(s):
 *  https://github.com/FellowTraveler/Moneychanger
 *  https://github.com/FellowTraveler/Open-Transactions/wiki
 *
 *  WEBSITE:
 *  http://www.OpenTransactions.org/
 *
 *  Components and licensing:
 *   -- Moneychanger..A Java client GUI.....LICENSE:.....GPLv3
 *   -- otlib.........A class library.......LICENSE:...LAGPLv3
 *   -- otapi.........A client API..........LICENSE:...LAGPLv3
 *   -- opentxs/ot....Command-line client...LICENSE:...LAGPLv3
 *   -- otserver......Server Application....LICENSE:....AGPLv3
 *  Github.com/FellowTraveler/Open-Transactions/wiki/Components
 *
 *  All of the above OT components were designed and written by
 *  Fellow Traveler, with the exception of Moneychanger, which
 *  was contracted out to Vicky C ([email protected]).
 *  The open-source community has since actively contributed.
 *
 *  -----------------------------------------------------
 *
 *   LICENSE:
 *   This program is free software: you can redistribute it
 *   and/or modify it under the terms of the GNU Affero
 *   General Public License as published by the Free Software
 *   Foundation, either version 3 of the License, or (at your
 *   option) any later version.
 *
 *   ADDITIONAL PERMISSION under the GNU Affero GPL version 3
 *   section 7: (This paragraph applies only to the LAGPLv3
 *   components listed above.) If you modify this Program, or
 *   any covered work, by linking or combining it with other
 *   code, such other code is not for that reason alone subject
 *   to any of the requirements of the GNU Affero GPL version 3.
 *   (==> This means if you are only using the OT API, then you
 *   don't have to open-source your code--only your changes to
 *   Open-Transactions itself must be open source. Similar to
 *   LGPLv3, except it applies to software-as-a-service, not
 *   just to distributing binaries.)
 *
 *   Extra WAIVER for OpenSSL, Lucre, and all other libraries
 *   used by Open Transactions: This program is released under
 *   the AGPL with the additional exemption that compiling,
 *   linking, and/or using OpenSSL is allowed. The same is true
 *   for any other open source libraries included in this
 *   project: complete waiver from the AGPL is hereby granted to
 *   compile, link, and/or use them with Open-Transactions,
 *   according to their own terms, as long as the rest of the
 *   Open-Transactions terms remain respected, with regard to
 *   the Open-Transactions code itself.
 *
 *   Lucre License:
 *   This code is also "dual-license", meaning that Ben Lau-
 *   rie's license must also be included and respected, since
 *   the code for Lucre is also included with Open Transactions.
 *   See Open-Transactions/src/otlib/lucre/LUCRE_LICENSE.txt
 *   The Laurie requirements are light, but if there is any
 *   problem with his license, simply remove the Lucre code.
 *   Although there are no other blind token algorithms in Open
 *   Transactions (yet. credlib is coming), the other functions
 *   will continue to operate.
 *   See Lucre on Github:  https://github.com/benlaurie/lucre
 *   -----------------------------------------------------
 *   You should have received a copy of the GNU Affero General
 *   Public License along with this program.  If not, see:
 *   http://www.gnu.org/licenses/
 *
 *   If you would like to use this software outside of the free
 *   software license, please contact FellowTraveler.
 *   (Unfortunately many will run anonymously and untraceably,
 *   so who could really stop them?)
 *
 *   DISCLAIMER:
 *   This program is distributed in the hope that it will be
 *   useful, but WITHOUT ANY WARRANTY; without even the implied
 *   warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
 *   PURPOSE.  See the GNU Affero General Public License for
 *   more details.

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 **************************************************************/

#include "stdafx.hpp"

#include "crypto/OTSubcredential.hpp"

#include "crypto/OTASCIIArmor.hpp"
#include "crypto/OTCredential.hpp"
#include "OTLog.hpp"
#include "OTStorage.hpp"

#include <irrxml/irrXML.hpp>

// Contains 3 key pairs: signing, authentication, and encryption.
// This is stored as an OTContract, and it must be signed by the
// master key. (which is also an OTSubcredential.)
//

namespace opentxs
{

void OTSubcredential::SetOwner(OTCredential& theOwner)
{
    m_pOwner = &theOwner;
}

OTSubcredential::OTSubcredential()
    : ot_super()
    , m_StoreAs(OTSubcredential::credPrivateInfo)
    , m_pOwner(nullptr)
{
    m_strContractType = "CREDENTIAL";
}

OTSubcredential::OTSubcredential(OTCredential& theOwner)
    : ot_super()
    , m_StoreAs(OTSubcredential::credPrivateInfo)
    , m_pOwner(&theOwner)
{
    m_strContractType = "CREDENTIAL";
}

OTSubcredential::~OTSubcredential()
{
    Release_Subcredential();
}

// virtual
void OTSubcredential::Release()
{
    Release_Subcredential(); // My own cleanup is done here.

    // Next give the base class a chance to do the same...
    ot_super::Release(); // since I've overridden the base class, I call it
                         // now...
}

void OTSubcredential::Release_Subcredential()
{
    // Release any dynamically allocated members here. (Normally.)
}

// virtual
bool OTSubcredential::SetPublicContents(const OTString::Map& mapPublic)
{
    m_mapPublicInfo = mapPublic;
    return true;
}

// virtual
bool OTSubcredential::SetPrivateContents(const OTString::Map& mapPrivate,
                                         const OTPassword*) // if not nullptr,
                                                            // it means to
                                                            // use this
                                                            // password by
                                                            // default.)
{
    m_mapPrivateInfo = mapPrivate;
    return true;
}

void OTSubcredential::SetMasterCredID(const OTString& strMasterCredID)
{
    m_strMasterCredID = strMasterCredID;
}

void OTSubcredential::SetNymIDandSource(const OTString& strNymID,
                                        const OTString& strSourceForNymID)
{
    m_strNymID = strNymID;
    m_strSourceForNymID = strSourceForNymID;
}

void OTSubcredential::UpdateMasterPublicToString(
    OTString& strAppendTo) // Used in UpdateContents.
{
    OT_ASSERT(nullptr != m_pOwner);
    OTASCIIArmor ascMaster(m_pOwner->GetPubCredential());
    strAppendTo.Concatenate("<masterPublic>\n%s</masterPublic>\n\n",
                            ascMaster.Get());
}

void OTSubcredential::UpdatePublicContentsToString(
    OTString& strAppendTo) // Used in UpdateContents.
{
    if (!m_mapPublicInfo.empty()) {
        strAppendTo.Concatenate("<publicContents count=\"%d\">\n\n",
                                m_mapPublicInfo.size());

        for (auto& it : m_mapPublicInfo) {
            OTString strInfo(it.second);
            OTASCIIArmor ascInfo(strInfo);
            strAppendTo.Concatenate(
                "<publicInfo key=\"%s\">\n%s</publicInfo>\n\n",
                it.first.c_str(), ascInfo.Get());
        }

        strAppendTo.Concatenate("</publicContents>\n\n");
    }
}

void OTSubcredential::UpdatePublicCredentialToString(
    OTString& strAppendTo) // Used in UpdateContents.
{
    if (GetContents().Exists()) {
        OTASCIIArmor ascContents(GetContents());
        if (ascContents.Exists())
            strAppendTo.Concatenate(
                "<publicCredential>\n%s</publicCredential>\n\n",
                ascContents.Get());
    }
}

void OTSubcredential::UpdatePrivateContentsToString(
    OTString& strAppendTo) // Used in UpdateContents.
{
    if (!m_mapPrivateInfo.empty()) {
        strAppendTo.Concatenate("<privateContents count=\"%d\">\n\n",
                                m_mapPrivateInfo.size());

        for (auto& it : m_mapPrivateInfo) {
            OTString strInfo(it.second);
            OTASCIIArmor ascInfo(strInfo);
            strAppendTo.Concatenate(
                "<privateInfo key=\"%s\">\n%s</privateInfo>\n\n",
                it.first.c_str(), ascInfo.Get());
        }
        strAppendTo.Concatenate("</privateContents>\n\n");
    }
}

void OTSubcredential::UpdateContents()
{
    m_xmlUnsigned.Release();

    m_xmlUnsigned.Concatenate(
        "<subCredential nymID=\"%s\"\n"     // a hash of the nymIDSource
        " masterCredentialID=\"%s\" >\n\n", // Hash of the master credential
                                            // that signed this subcredential.
        GetNymID().Get(),
        GetMasterCredID().Get());

    if (GetNymIDSource().Exists()) {
        OTASCIIArmor ascSource;
        ascSource.SetString(GetNymIDSource()); // A nym should always
                                               // verify through its own
                                               // source. (Whatever that
                                               // may be.)
        m_xmlUnsigned.Concatenate("<nymIDSource>\n%s</nymIDSource>\n\n",
                                  ascSource.Get());
    }

    //  if (OTSubcredential::credPublicInfo == m_StoreAs)  // (Always saving
    // public info.)
    {
        // PUBLIC INFO
        UpdateMasterPublicToString(m_xmlUnsigned);

        UpdatePublicContentsToString(m_xmlUnsigned);
    }

    // If we're saving the private credential info...
    //
    if (OTSubcredential::credPrivateInfo == m_StoreAs) {
        UpdatePublicCredentialToString(m_xmlUnsigned);

        UpdatePrivateContentsToString(m_xmlUnsigned);
    }
    // -------------------------------------------------
    m_xmlUnsigned.Concatenate("</subCredential>\n");

    m_StoreAs = OTSubcredential::credPrivateInfo; // <=== SET IT BACK TO DEFAULT
                                                  // BEHAVIOR. Any other state
                                                  // processes ONCE, and then
                                                  // goes back to this again.
}

// return -1 if error, 0 if nothing, and 1 if the node was processed.
//
int32_t OTSubcredential::ProcessXMLNode(irr::io::IrrXMLReader*& xml)
{
    int32_t nReturnVal = 0;

    const OTString strNodeName(xml->getNodeName());

    // Here we call the parent class first.
    // If the node is found there, or there is some error,
    // then we just return either way.  But if it comes back
    // as '0', then nothing happened, and we'll continue executing.
    //
    // -- Note you can choose not to call the parent if
    // you don't want to use any of those xml tags.
    // As I do in the case of OTAccount.
    //
    // if (nReturnVal = OTContract::ProcessXMLNode(xml))
    //      return nReturnVal;

    if (strNodeName.Compare("subCredential")) {
        m_strNymID = xml->getAttributeValue("nymID");
        m_strMasterCredID = xml->getAttributeValue("masterCredentialID");

        otWarn << "Loading subcredential...\n";

        nReturnVal = 1;
    }
    else if (strNodeName.Compare("nymIDSource")) {
        otWarn << "Loading nymIDSource...\n";

        OTASCIIArmor ascTemp;
        if (!OTContract::LoadEncodedTextField(xml, ascTemp)) {
            otErr << "Error in " << __FILE__ << " line " << __LINE__
                  << ": failed loading expected nymIDSource field.\n";
            return (-1); // error condition
        }
        if (ascTemp.Exists()) ascTemp.GetString(m_strSourceForNymID);

        nReturnVal = 1;
    }
    else if (strNodeName.Compare("masterPublic")) {
        OTString strMasterPublicCredential;

        if (false ==
            OTContract::LoadEncodedTextField(xml, strMasterPublicCredential)) {
            otErr << "Error in " << __FILE__ << " line " << __LINE__
                  << ": failed loading expected master public credential while "
                     "loading subcredential.\n";
            return (-1); // error condition
        }
        // Verify the master public credential we loaded against the one we
        // expected to get, according
        // to the OTCredential that is m_pOwner.
        //
        else if ((nullptr != m_pOwner) &&
                 false == (m_pOwner->GetPubCredential().Compare(
                              strMasterPublicCredential))) {
            otErr << "Failure in " << __FILE__ << " line " << __LINE__
                  << ": while loading subcredential: master public "
                     "credential loaded just now, doesn't match the actual "
                     "master public credential, "
                     "according to the current owner object.\n";
            return (-1); // error condition
        }

        nReturnVal = 1;
    }
    else if (strNodeName.Compare("publicContents")) {
        OTString strCount;
        strCount = xml->getAttributeValue("count");
        const int32_t nCount = strCount.Exists() ? atoi(strCount.Get()) : 0;
        if (nCount > 0) {
            int32_t nTempCount = nCount;
            OTString::Map mapPublic;

            while (nTempCount-- > 0) {

                const char* pElementExpected = "publicInfo";
                OTString strPublicInfo;

                // This map contains values we will also want, when we read the
                // info...
                // (The OTContract::LoadEncodedTextField call below will read
                // all the values
                // as specified in this map.)
                //
                OTString::Map temp_MapAttributes;
                temp_MapAttributes.insert(std::pair<std::string, std::string>(
                    "key",
                    "")); // Value should be "A" or "E" or "S" after reading.

                if (!OTContract::LoadEncodedTextFieldByName(
                        xml, strPublicInfo, pElementExpected,
                        &temp_MapAttributes)) // </publicInfo>
                {
                    otErr << __FUNCTION__ << ": Error: Expected "
                          << pElementExpected << " element with text field.\n";
                    return (-1); // error condition
                }

                auto it = temp_MapAttributes.find("key");
                if ((it != temp_MapAttributes.end())) // We expected this much.
                {
                    std::string& str_key = it->second;

                    if (str_key.size() >
                        0) // Success finding key type ('A' 'E' or 'S')
                    {

                        mapPublic.insert(std::pair<std::string, std::string>(
                            str_key, strPublicInfo.Get()));

                    }
                    // else it's empty, which is expected if nothing was there,
                    // since that's the default value
                    // that we set above for "name" in temp_MapAttributes.
                    else {
                        otErr << __FUNCTION__
                              << ": Expected key type of 'A' or 'E' or 'S'.\n";
                        return (-1); // error condition
                    }
                }
                else {
                    otErr << __FUNCTION__
                          << ": Strange error: couldn't find key type AT "
                             "ALL.\n"; // should never happen.
                    return (-1);       // error condition
                }
            } // while

            if (static_cast<int64_t>(mapPublic.size()) != nCount) {
                otErr << __FUNCTION__ << ", " << __FILE__ << ", " << __LINE__
                      << ": Subcredential expected to load " << nCount
                      << " publicInfo objects, "
                         "but actually loaded " << mapPublic.size()
                      << ". (Mismatch, failure loading.)\n";
                return (-1); // error condition
            }

            if (false ==
                SetPublicContents(mapPublic)) // <==============  Success.
            {
                otErr << __FUNCTION__ << ", " << __FILE__ << ", " << __LINE__
                      << ": Subcredential failed setting public contents while "
                         "loading.\n";
                return (-1); // error condition
            }

        } // if strCount.Exists() && nCount > 0

        otInfo << "Loaded publicContents for subcredential.\n";

        nReturnVal = 1;
    }
    else if (strNodeName.Compare("publicCredential")) {
        if (!OTContract::LoadEncodedTextField(
                xml, m_strContents)) // <========= m_strContents.
        {
            otErr << "Error in " << __FILE__ << " line " << __LINE__
                  << ": failed loading expected public credential while "
                     "loading private subcredential.\n";
            return (-1); // error condition
        }

        nReturnVal = 1;
    }
    else if (strNodeName.Compare("privateContents")) {
        OTString strCount;
        strCount = xml->getAttributeValue("count");
        const int32_t nCount = strCount.Exists() ? atoi(strCount.Get()) : 0;
        if (nCount > 0) {
            int32_t nTempCount = nCount;
            OTString::Map mapPrivate;

            while (nTempCount-- > 0) {

                const char* pElementExpected = "privateInfo";
                OTString strPrivateInfo;

                // This map contains values we will also want, when we read the
                // info...
                // (The OTContract::LoadEncodedTextField call below will read
                // all the values
                // as specified in this map.)
                //
                OTString::Map temp_MapAttributes;
                temp_MapAttributes.insert(std::pair<std::string, std::string>(
                    "key",
                    "")); // Value should be "A" or "E" or "S" after reading.

                if (!OTContract::LoadEncodedTextFieldByName(
                        xml, strPrivateInfo, pElementExpected,
                        &temp_MapAttributes)) // </privateInfo>
                {
                    otErr << __FUNCTION__ << ": Error: Expected "
                          << pElementExpected << " element with text field.\n";
                    return (-1); // error condition
                }

                auto it = temp_MapAttributes.find("key");
                if ((it != temp_MapAttributes.end())) // We expected this much.
                {
                    std::string& str_key = it->second;

                    if (str_key.size() >
                        0) // Success finding key type ('A' 'E' or 'S')
                    {

                        mapPrivate.insert(std::pair<std::string, std::string>(
                            str_key, strPrivateInfo.Get()));

                    }
                    // else it's empty, which is expected if nothing was there,
                    // since that's the default value
                    // that we set above for "name" in temp_MapAttributes.
                    else {
                        otErr << __FUNCTION__
                              << ": Expected key type of 'A' or 'E' or 'S'.\n";
                        return (-1); // error condition
                    }
                }
                else {
                    otErr << __FUNCTION__
                          << ": Strange error: couldn't find key type AT "
                             "ALL.\n"; // should never happen.
                    return (-1);       // error condition
                }
            } // while

            if (static_cast<int64_t>(mapPrivate.size()) != nCount) {
                otErr << __FUNCTION__ << ", " << __FILE__ << ", " << __LINE__
                      << ": Subcredential expected to load " << nCount
                      << " privateInfo objects, "
                         "but actually loaded " << mapPrivate.size()
                      << ". (Mismatch, failure loading.)\n";
                return (-1); // error condition
            }

            OT_ASSERT(nullptr != m_pOwner);

            // Sometimes we are supposed to use a specific, pre-specified
            // password (versus just
            // blindly asking the user to type a password when it's not cached
            // alrady.) For example,
            // when importing a Nym, the exported version of the Nym is not
            // encrypted to the cached
            // wallet key. It's got its own exported passphrase. So it won't be
            // cached, and we will have
            // the wallet's cached key disabled while loading it. This means we
            // have to enter the same
            // passphrase many times in a row, while OT loads up all the
            // credentials and keys for that
            // Nym. Therefore, instead, we ask the user up front to enter the
            // special passphrase for that
            // exported Nym. Then we just pass it in to all the functions that
            // need it, so none of them have
            // to ask the user to type it.
            //
            // That's what brings us here now... when that happens,
            // m_pOwner->GetImportPassword() will be set
            // with the appropriate pointer to the passphrase. Otherwise it will
            // be nullptr. Meanwhile SetPrivateContents
            // below accepts an import passphrase, which it defaults to nullptr.
            //
            // So we just pass it in either way (sometimes it's nullptr and the
            // wallet cached master key is used, and
            // sometimes an actual passphrase is passed in, so we use it.)

            if (false ==
                SetPrivateContents(mapPrivate, m_pOwner->GetImportPassword())) {
                otErr << __FUNCTION__ << ", " << __FILE__ << ", " << __LINE__
                      << ": Subcredential failed setting private contents "
                         "while loading.\n";
                return (-1); // error condition
            }

        } // if strCount.Exists() && nCount > 0

        otInfo << "Loaded privateContents for subcredential.\n";

        nReturnVal = 1;
    }

    return nReturnVal;
}

bool OTSubcredential::SaveContractWallet(std::ofstream&) const
{
    return false;
}

// VERIFICATION

// Verify that m_strNymID is the same as the hash of m_strSourceForNymID.
//
bool OTSubcredential::VerifyNymID() const
{

    // Verify that m_strNymID is the same as the hash of m_strSourceForNymID.
    //
    OTIdentifier theTempID;
    const bool bCalculate = theTempID.CalculateDigest(m_strSourceForNymID);
    OT_ASSERT(bCalculate);

    const OTString strNymID(theTempID);
    if (!m_strNymID.Compare(strNymID)) {
        otOut << __FUNCTION__
              << ": Failure: When the NymID's source is hashed, the result "
                 "doesn't match the expected NymID.\n"
                 "Expected: " << m_strNymID << "\n   Found: " << strNymID
              << "\n  Source: " << m_strSourceForNymID << "\n";
        return false;
    }

    return true;
}

// Call VerifyNymID. Then verify m_strMasterCredID against the hash of
// m_pOwner->GetMasterkey().GetPubCredential() (the master credential.) Verify
// that
// m_pOwner->GetMasterkey() and *this have the same NymID. Then verify the
// signature of m_pOwner->GetMasterkey().
//
bool OTSubcredential::VerifyInternally()
{
    OT_ASSERT(nullptr != m_pOwner);

    // Verify that m_strNymID is the same as the hash of m_strSourceForNymID.
    //
    if (!VerifyNymID()) return false;

    // Verify that m_pOwner->GetMasterkey() and *this have the same NymID.
    //
    if (!m_strNymID.Compare(m_pOwner->GetMasterkey().GetNymID())) {
        otOut << __FUNCTION__
              << ": Failure: The actual master credential's NymID doesn't "
                 "match the NymID on this subcredential.\n"
                 "    This NymID: " << m_strNymID
              << "\nMaster's NymID: " << m_pOwner->GetMasterkey().GetNymID()
              << "\n My Master Cred ID: " << m_strMasterCredID << "\n";
        return false;
    }

    // Verify m_strMasterCredID against the hash of
    // m_pOwner->GetMasterkey().GetPubCredential()
    // (the master credentialID is a hash of the master credential.)
    //
    OTIdentifier theActualMasterID;
    const bool bCalcMasterCredID =
        theActualMasterID.CalculateDigest(m_pOwner->GetPubCredential());
    OT_ASSERT(bCalcMasterCredID);
    const OTString strActualMasterID(theActualMasterID);

    if (!m_strMasterCredID.Compare(strActualMasterID)) {
        otOut << __FUNCTION__
              << ": Failure: When the actual Master Credential is hashed, the "
                 "result doesn't match the expected Master Credential ID.\n"
                 "Expected: " << m_strMasterCredID
              << "\n   Found: " << strActualMasterID << "\nMaster Cred:\n"
              << m_pOwner->GetPubCredential() << "\n";
        return false;
    }

    // Then verify the signature of m_pOwner->GetMasterkey()...
    // Let's get a few things straight:
    // * OTMasterkey is a key (derived from OTKeyCredential, derived from
    // OTSubcredential) and it can only sign itself.
    // * The only further verification a Masterkey can get is if its hash is
    // posted at the source. Or, if the source
    //   is a public key, then the master key must be signed by the
    // corresponding private key. (Again: itself.)
    // * Conversely to a master key which can ONLY sign itself, all subkeys must
    // ALSO sign themselves.
    //
    // * Thus: Any OTKeyCredential (both master and subkeys, but no other
    // credentials) must ** sign itself.**
    // * Whereas m_strMasterSigned is only used by OTSubkey, and thus only must
    // be verified there.
    // * Any OTSubcredential must also be signed by its master. (Except masters,
    // which already sign themselves.)
    // * Any OTMasterkey must (at some point, and/or regularly) verify against
    // its own source.

    // * Any OTSubcredential must also be signed by its master. (Except masters,
    // which already sign themselves.)
    //
    if (!VerifySignedByMaster()) {
        otOut << __FUNCTION__ << ": Failure: This subcredential hasn't been "
                                 "signed by its master credential.\n";
        return false;
    }

    return true;
}

bool OTSubcredential::VerifySignedByMaster()
{
    OT_ASSERT(nullptr != m_pOwner);
    return VerifyWithKey(m_pOwner->GetMasterkey().m_SigningKey.GetPublicKey());
}

bool OTSubcredential::VerifyContract()
{
    if (!VerifyContractID()) {
        otWarn << __FUNCTION__ << ": Failed verifying credential ID against "
                                  "whatever it was expected to be.\n";
        return false;
    }

    if (!VerifyInternally()) // Logs copiously.
        return false;

    return true;
}

// Overriding from OTContract.
void OTSubcredential::CalculateContractID(OTIdentifier& newID) const
{
    if (!newID.CalculateDigest(GetPubCredential()))
        otErr << __FUNCTION__ << ": Error calculating credential digest.\n";
}

// I needed this for exporting a Nym (with credentials) from the wallet.
const OTString& OTSubcredential::GetPriCredential() const
{
    OT_ASSERT_MSG(!m_mapPrivateInfo.empty(), "ASSERT: GetPriCredential can "
                                             "only be called on private "
                                             "subcredentials.");

    return m_strRawFile;
}

// We don't want to have to figure this out each time we need the public
// credential, so we just
// call this function wherever we need to get the public credential.
//
const OTString& OTSubcredential::GetPubCredential() const // More intelligent
                                                          // version of
                                                          // GetContents. Higher
                                                          // level.
{
    // If this is a private (client-side) credential containing private keys,
    // then the public version is stored in GetContents(), and return that.
    if ((!m_mapPrivateInfo.empty()) && GetContents().Exists())
        return GetContents();

    // Otherwise this is a server-side copy of a Nym's credential, with no
    // private keys inside it.
    // In which case public info that would have been in GetContents (making
    // room so we can have
    // the private keys in m_strRawFile) is now directly found in m_strRawFile,
    // since that's all the
    // server ever loads up. There is only public info and nothing else, so it's
    // found in the main
    // normal location, m_strRawFile.
    //
    return m_strRawFile;
}

} // namespace opentxs